A Creative Introduction to Entropy

February 13, 2012

By Dr. D. Zietlow & Dr. Jacqueline Henderson

A pedagogical tool to explain entropy and the second law of thermodynamics was developed through collaboration between art, The League of Imaginary Scientists and mechanical engineering. This tool can also be used as the introduction to a discussion on some of the issues that help students understand the ethical and global issues that our society faces. One of the outcomes of the collaboration included a multi-level, interactive art installation. The participant of the exhibit stands on a platform and simulates an earthquake which causes blocks from buildings to fall. Each block is connected to a switch which activates a fan when it falls. The fan levitates a ping-pong ball which graphically represents the level of disorder, or entropy, resulting from the earthquake. To restore order, the participate needs to replace the blocks at which time the switch opens the circuit to the fan causing the balls to drop. Another product of this collaboration was a video, ninety-nine seconds in duration, explaining entropy using the exhibit. The video at http://youtu.be/30FikBLf0UA can be used as a pedagogical tool in any classroom across all disciplines. It can be used to initiate discussion topics such as ethical and global issues facing society. Entropy can be used as a portal into some of the deeper issues of life by asking the following questions: 1) what is the cause of disorder, 2) do we live in an isolated system, and 3) how can order be restored?

A multiple choice test was developed to measure students understanding of entropy after visiting the exhibit. The test was administered to freshman, sophomores, juniors and seniors in three different courses. The vast majority (90%) of the sophomores and juniors currently in the first semester of thermodynamics, had been exposed the second law of thermodynamics and entropy in high school and college science classes. In addition to this the heat transfer students had two semesters of thermodynamics. In comparison, the freshman had minimal exposure (50%) to thermodynamics in high school science classes. The test not only sampled their understanding of how entropy relates to mechanical systems but also health, interpersonal and international relations. The results show that most of the students properly understood the definition of entropy with a mean score above 80% for all the courses. Understanding improved from 8 to 10 percentage points with additional requirements to write an essay and another 3 to 6 percentage points with a 50 minute lecture. Integrate experiential learning into pedagogy whenever possible.